BICE – Global Change, Biotic Interactions, and Plants Invasions in Cold Environment

Alpine ecosystems are considered among the most vulnerable to global change. In the last decades, in the Alps temperatures have increased by about 1°C and the landscapes have been radically transformed. At low elevations urban and agricultural areas have increased, while at intermediate elevations grasslands have been abandoned and replaced by forests.

In the BICE project, we have shown how the combined effect of climate change and landscape transformation causes both the decline of rare species and the invasion of invasive exotic species with negative consequences on biodiversity. In particular, in a study published in the prestigious journal Nature Communications, we described dramatic demographic declines for about two thirds of alpine orchid species, which are often unable to respond to climate warming (https://www.nature.com/articles/s41467-020-19680-2).

On the contrary, the same processes that lead rare species to extinction are favouring the invasions of exotic species that are spreading faster from disturbed low-elevation areas to more pristine alpine habitats. In particular, we showed that most exotic plants are favoured by warming temperatures and soil disturbance related to infrastructure construction. Finally, several studies in the BICE project have also proved how the pressure from herbivorous insects can modify the invasion dynamics of exotic plants and how these invasions can alter ecological interaction networks between native plants and pollinators. In conclusion, the BICE project pointed out the fragility of Alpine ecosystems to global change and the need to introduce measures to mitigate the negative effects of both climate and land use change.